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[Python-Dev] Capabilities in Python

Jim Fulton jim@zope.com
Mon, 10 Mar 2003 06:31:16 -0500 
Guido van Rossum wrote:
> [Jim]
> 
>>You don't need restricted execution to make proxies work.
> 
> 
> Um, I think that's a dangerous mistake, or a confusion in terminology.

All I'm saying is that the proxy mechanism itself doesn't rely on
restricted execution.

> Without restricted execution, untrusted code would have access to
> sys.modules, and from there it would be able to access
> removeAllProxies.

All we need to be able to do is control imports.  It turns out that
to prevent access to sys.modules, we have to replace __builtins__,
which has the side-effect of enabling restricted execution. You
don't need anything but the ability to restrict imports and other
unproxied access to sys.modules to use proxies.

Jim

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